Messi and Ronaldo have only three goals between them in World Cup finals

To claim that Lionel Messi or Cristiano Ronaldo are somehow lacking something as footballers seems almost perverse.

These are the twin tornados of today's football landscape, chasing each other in a statistical arms race, tearing up records, making the impossible mundane.

But as their third World Cups come around, there remains a sense of incompleteness, of a final summit still to climb.

What separates Argentina's Messi and Portugal's Ronaldo from footballing immortality? Certainly not goals, whether in quantity or style, or club honours, or individual accolades won. By those measures both match Pele and Maradona, arguably surpass Zinedine Zidane and Johan Cruyff.

What it is missing is a World Cup: not a brilliant solo goal, nor a single great win, but a tournament that they have dominated and defined.

Media playback is not supported on this device

Great World Cup moments: Magnificent Pele

Diego Maradona achieved that grail in 1986, dancing and driving Argentina to the title. Pele perhaps did it twice, as spearhead in 1958 and embodiment of his team's brilliance 12 years later. Even in defeat Cruyff (1974) and Roberto Baggio (1994) owned a tournament.

This is the power of a World Cup. Reputations are transformed. Legacies are gilded.

"Mexico changed my life, quite literally," says Gary Lineker, whose six goals won him the Golden Boot in 1986. "It made a massive difference to me - a player going from one who was not assured of a starting place in the England team to suddenly, after that World Cup, being known by everybody wherever I went."

Messi and Ronaldo have achieved far more in club football than Lineker. Between them they have five Champions League trophies and all six of the last Fifa World Player of the Year or Ballon D'Or awards.

Unlike Lineker they are already global superstars. Yet unlike the former England striker, or his successor as Golden Boot winner, Italy's Toto Schillaci, they lack such a clearly defined peak.

Deep into their careers, at an age where pace and influence are yet to fade, they will never have a better chance.

Media playback is not supported on this device

Messi more of a team player - Lineker

In 571 minutes at World Cup finals Messi has scored just one goal, the same number as Matthew Upson and Gary Breen. In 754 minutes, Ronaldo has only one more than the England and Ireland centre-halves. To put that into goalscoring context, Denmark's comparatively prosaic forward Jon Dahl Tomasson has five. Pele ended with 12, and the Brazilian Ronaldo had 15.

"For the true greats of all time, you have got to make a name for yourself at a World Cup, if you are lucky enough to have been born in a country where you can," says Lineker.

"If you are a great player for a country like Argentina, Italy, Germany or England you've got to prove it at a World Cup - not necessarily to win it, but to make yourself one of the greats of that tournament.

"It is probably the one thing that counts against Messi at the moment when set against the likes of Pele and Maradona. He has not got that World Cup under his belt - but neither had Maradona until he came to this stage of his career. Maybe Messi will now do the same."

In some ways it's a cruel yardstick. World Cups, by definition, are only a periodic barometer of greatness.

Some of the finest players in history have been denied the opportunity to display at the greatest expo of all, whether through nationality (George Best, Alfredo di Stefano, George Weah), injury and insult (Bernd Schuster) or tragedy (Duncan Edwards, Valentino Mazzola).

Others have peaked in intervening years, been dragged down by less liberated team-mates or found themselves neutered by the sort of dedicated on-field attention that the most dangerous opponent routinely attracts. All three could yet happen to Ronaldo and Messi.

In the 21st century, there is an argument that the Champions League is a more accurate gauge of a superstar's influence: more matches, more sustained pressure, a higher and more consistent calibre of opposition.

Media playback is not supported on this device

World Cup moments: 'Pure football genius'

Messi has three winner's medals from European club football's greatest competition, Ronaldo one each from two clubs. In each triumph, each man played a pivotal role; both have scored key goals in two separate finals.

These feats are not achieved by many, let alone the ordinary. And while the Champions League final attracts a far smaller global audience than the World Cup (the 2013 final had an average audience of 150 million, the 2010 World Cup final six times that) its cumulative reach across four years narrows the gap.

Then there is over-familiarity that modern media saturation can bring. Very few of us have seen Pele live, whether in person or on television. Even Maradona we know primarily from World Cups and video compilations.

You can watch Ronaldo and Messi every week, should you have the right satellite subscription. You can watch them at any moment via video-sharing sites on your mobile and tablet.

Has this removed the untouchable aura that surrounds their antecedents? Do we associate Pele with genius because 'best ofs', by definition, do not include the average or off-form?

Head to Head

Lionel Messi

Cristiano Ronaldo

Date of birth (age)

24 June, 1987 (26)

5 February, 1985 (29)

Clubs played for

Barcelona

Sporting Lisbon, Manchester United, Real Madrid

Total league matches played

277

386

Total league goals scored

243

264

International debut

17 August, 2005 v Hungary

20 August, 2003 v Kazakhstan

Caps

84

110

International goals

37

49

Club honours

Six league titles, three Champions Leagues, two domestic cups, two Club World Cups

Four league titles, two Champions Leagues, three domestic cups, one Club World Cup

Individual honours

Four Ballon d'Or awards

Two Ballon d'Or awards

The caveat most often used by those wishing to contextualise the remarkable goal-scoring feats of today's two prodigies is that the currency of the Primera Liga is devalued, in part by the financial dominance of Real Madrid and Barcelona and thus in part also their on-pitch supremacy.

In which case, Pele's famous 1,283 goals in 1,366 appearances for Santos, Brazil and New York Cosmos are the equivalent of old copper coins - some invaluable, some (like those accrued in endless friendlies and promotional matches) near worthless.

Were the defences that Pele came up against as organised and fit as those that face Messi and Ronaldo? Are those two free to work their magic in a way that the often brutalised Maradona never was?

Which is why we come back to the World Cup. You can only judge a man in his historical context. Pele and Maradona made tournaments their own. Messi and Ronaldo, deferential to their sport's past, understand instinctively.

"Messi would give all the medals he has won at Barcelona to win one World Cup," says Argentina's 1978 World Cup winner Osvaldo Ardiles. Ronaldo already has his own museum in which to house the greatest honour of them all.

Could Messi, Ronaldo or home favourite Neymar prove the defining figure in Brazil?

Providence and history call for both.

For Ronaldo, his country's captain, the astonishingly dominant force in their qualification (all four goals in Portugal's play-off against Sweden came from their number seven), 29 years and 110 caps into his career arc, now is the time - not in 2018, never again.

For Messi, less adored at home than the ragamuffin talents of Maradona or even Carlos Tevez, serendipity is on his side.

Argentina coach Alex Sabella has built his team around the Barcelona man in a way that his predecessor in 2010, Maradona, never did.

Media playback is not supported on this device

Can Lionel Messi achieve greatness in Brazil?

And with the tournament hosted by his nation's arch-rivals, politics and culture are on his side too - not quite as they were for Zidane in 1998, when his ethnic origins as much as his two headers in the final made him the incarnation of the 'Black Blanc Beur' philosophy, but in a way that creates the perfect backstory for his deeds.

Only one, of course, could win the old gold pot. So what will be enough - a glorious but doomed soliloquy, as with Baggio two decades ago, or a semi-final, perhaps the Golden Boot?

Should one be crowned world champion, it might even be enough to swing the eternal argument about which is the superior player. That's what World Cups can do: complete careers, crown kings.